Build Text instances in a declarative manner, similar to regular views, from Text and Image. This ensures the font’s kerning, ligatures, and other properties are preserved across the entire text.

TextBuilder.swift

//
//  TextBuilder.swift
//  
//
//  Created by Valentin Walter on 14.02.23.
//

import SwiftUI

/// Build Text instances in a declarative manner, similar to regular views, from
/// Text and Image. This ensures the font’s kerning, ligatures, and other
/// properties are preserved across the entire text.
///
/// Example
///
/// ```swift
/// Text {
///     for index in 0..<10 {
///         Image(systemName: "\(index).circle")
///             .foregroundColor(.secondary)
///     }
///
///     if showLabel {
///         Text(label)
///             .font(.headline)
///     }
/// }
/// ```
///
@resultBuilder
public struct TextBuilder {
    @inlinable
    public static func buildBlock(_ components: Text...) -> Text {
        buildArray(components)
    }
    
    @inlinable
    public static func buildArray(_ components: [Text]) -> Text {
        components.dropFirst().reduce(components.first ?? Text(""), +)
    }
    
    @inlinable
    public static func buildEither(first component: Text) -> Text {
        component
    }
    
    @inlinable
    public static func buildEither(second component: Text) -> Text {
        component
    }
    
    @inlinable
    public static func buildOptional(_ component: Text?) -> Text {
        component ?? Text("")
    }
    
    @inlinable
    public static func buildExpression(_ image: Image) -> Text {
        Text("\(image)")
    }
    
    @inlinable
    public static func buildExpression(_ text: Text) -> Text {
        text
    }
}

extension Text {
    /// Build `Text` instances in a declarative manner, similar to regular
    /// views, from `Text` and `Image`. This ensures the font's kerning,
    /// ligatures, and other properties are preserved across the entire text.
    ///
    /// Example
    ///
    /// ```swift
    /// Text {
    ///     for index in 0..<10 {
    ///         Image(systemName: "\(index).circle")
    ///             .foregroundColor(.secondary)
    ///     }
    ///
    ///     if showLabel {
    ///         Text(label)
    ///             .font(.headline)
    ///     }
    /// }
    /// ```
    ///
    public init(@TextBuilder content: () -> Text) {
        self = content()
    }
}

// MARK: - Auxiliary

extension Image {
    @inlinable
    public func foregroundColor(_ color: Color?) -> Text {
        Text("\(self)").foregroundColor(color)
    }
}

// MARK: - Previews

struct TextBuilder_Previews: PreviewProvider {
    static var previews: some View {
        let showLabel = true
        
        Text {
            for index in 0..<4 {
                Image(systemName: "\(index).circle")
                    .foregroundColor(.secondary)
            }
            
            Text(" ")
            
            if showLabel {
                Text("Label")
                    .font(.headline)
            }
        }
    }
}